The objective of this work is to determine Lecithin:Cholesterol Acyltransferase in human plasma. Since we have been able to produce an antiserum to highly purified LCAT we shall start working on immunoassay of the enzyme in human plasma under various nutritional and pathological states. Radial-immunodiffusion, electroimmunoassay and radio-immunoassay will be developed to estimate the enzyme per se in human plasma.